After publication of the original article [1], the authors noticed the Acknowledgements section was incorrect as follows: “This works was supported by National Research Foundation (NRF) of Korea Grant funded by the Korean Governments by the Korea government (MSIP) [2013R1A1A2011999], [NRF-2013R1A2A2A01067194], and [2011-0030130]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.”

The correct version of the Acknowledgements section is included below:

Acknowledgements

This paper was sponsored by Joosan Scholarship Foundation of Wonkwang University in 2014.

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